As disclosed in Sterling Drug's U.S. Pat. No. 3,753,993 (Lesher et al.), 3,907,808 (Lesher and Carabateas), and 4,118,557 (Lesher), it is known that antibacterial 1-alkyl-1,4-dihydro-4-oxo-7-pyridinyl-3-quinolinecarboxylic acids can be prepared from 4-(3-aminophenyl)pyridine. Lesher et al. and Lesher and Carabateas show that their 4-(3-aminophenyl)pyridine is synthesized from 4-(3-nitrophenyl)pyridine, and U.S. Pat. Nos. 3,970,662 (Carabateas and Williams) and 3,994,903 (Carabateas and Brundage) -- assigned to the same assignee as Lesher, Lesher et al., and Lesher and Carabateas -- indicate that Lesher et al. and Lesher and Carabateas used uneconomical processes for preparing their 4-(3-nitrophenyl) pyridine.
Copending application Ser. No. 300,046, filed Sept. 8, 1981, in the name of Thomas J. Walter, discloses a desirable process for preparing 4-(chlorophenyl)pyridines, including 4-(3-chlorophenyl)pyridine and 4-(4-chlorophenyl)pyridine, and also teaches that these compounds are useful as intermediates in the synthesis of the antibacterial products of Lesher et al. and Lesher and Carabateas.